Commit 28077125 authored by Eric Auger's avatar Eric Auger Committed by Christoffer Dall
Browse files

KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES 



This patch adds a new attribute to GICV3 KVM device
KVM_DEV_ARM_VGIC_GRP_CTRL group. This allows userspace to
flush all GICR pending tables into guest RAM.

Signed-off-by: default avatarEric Auger <eric.auger@redhat.com>
Reviewed-by: default avatarChristoffer Dall <cdall@linaro.org>
Acked-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
parent ccb1d791

arch/arm/include/uapi/asm/kvm.h

+1 −0
Original line number Diff line number Diff line
@@ -204,6 +204,7 @@ struct kvm_arch_memory_slot { 
#define   KVM_DEV_ARM_VGIC_CTRL_INIT		0

#define   KVM_DEV_ARM_ITS_SAVE_TABLES		1

#define   KVM_DEV_ARM_ITS_RESTORE_TABLES	2

#define   KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES	3



/* KVM_IRQ_LINE irq field index values */

#define KVM_ARM_IRQ_TYPE_SHIFT		24

arch/arm64/include/uapi/asm/kvm.h

+1 −0
Original line number Diff line number Diff line
@@ -224,6 +224,7 @@ struct kvm_arch_memory_slot { 
#define   KVM_DEV_ARM_VGIC_CTRL_INIT		0

#define   KVM_DEV_ARM_ITS_SAVE_TABLES           1

#define   KVM_DEV_ARM_ITS_RESTORE_TABLES        2

#define   KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES	3



/* Device Control API on vcpu fd */

#define KVM_ARM_VCPU_PMU_V3_CTRL	0

virt/kvm/arm/vgic/vgic-kvm-device.c

+20 −0
Original line number Diff line number Diff line
@@ -580,6 +580,24 @@ static int vgic_v3_set_attr(struct kvm_device *dev, 
		reg = tmp32;

		return vgic_v3_attr_regs_access(dev, attr, &reg, true);

	}

	case KVM_DEV_ARM_VGIC_GRP_CTRL: {

		int ret;



		switch (attr->attr) {

		case KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES:

			mutex_lock(&dev->kvm->lock);



			if (!lock_all_vcpus(dev->kvm)) {

				mutex_unlock(&dev->kvm->lock);

				return -EBUSY;

			}

			ret = vgic_v3_save_pending_tables(dev->kvm);

			unlock_all_vcpus(dev->kvm);

			mutex_unlock(&dev->kvm->lock);

			return ret;

		}

		break;

	}

	}

	return -ENXIO;

}
@@ -658,6 +676,8 @@ static int vgic_v3_has_attr(struct kvm_device *dev, 
		switch (attr->attr) {

		case KVM_DEV_ARM_VGIC_CTRL_INIT:

			return 0;

		case KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES:

			return 0;

		}

	}

	return -ENXIO;

virt/kvm/arm/vgic/vgic-v3.c

+51 −0
Original line number Diff line number Diff line
@@ -278,6 +278,57 @@ int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq) 
	return 0;

}



/**

 * vgic_its_save_pending_tables - Save the pending tables into guest RAM

 * kvm lock and all vcpu lock must be held

 */

int vgic_v3_save_pending_tables(struct kvm *kvm)

{

	struct vgic_dist *dist = &kvm->arch.vgic;

	int last_byte_offset = -1;

	struct vgic_irq *irq;

	int ret;



	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {

		int byte_offset, bit_nr;

		struct kvm_vcpu *vcpu;

		gpa_t pendbase, ptr;

		bool stored;

		u8 val;



		vcpu = irq->target_vcpu;

		if (!vcpu)

			continue;



		pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);



		byte_offset = irq->intid / BITS_PER_BYTE;

		bit_nr = irq->intid % BITS_PER_BYTE;

		ptr = pendbase + byte_offset;



		if (byte_offset != last_byte_offset) {

			ret = kvm_read_guest(kvm, ptr, &val, 1);

			if (ret)

				return ret;

			last_byte_offset = byte_offset;

		}



		stored = val & (1U << bit_nr);

		if (stored == irq->pending_latch)

			continue;



		if (irq->pending_latch)

			val |= 1 << bit_nr;

		else

			val &= ~(1 << bit_nr);



		ret = kvm_write_guest(kvm, ptr, &val, 1);

		if (ret)

			return ret;

	}

	return 0;

}



/* check for overlapping regions and for regions crossing the end of memory */

static bool vgic_v3_check_base(struct kvm *kvm)

{

virt/kvm/arm/vgic/vgic.h

+1 −0
Original line number Diff line number Diff line
@@ -173,6 +173,7 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu); 
int vgic_v3_probe(const struct gic_kvm_info *info);

int vgic_v3_map_resources(struct kvm *kvm);

int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq);

int vgic_v3_save_pending_tables(struct kvm *kvm);

int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t dist_base_address);



void vgic_v3_load(struct kvm_vcpu *vcpu);